An Atlantic County couple was charged today with killing their 7-week-old child by giving the baby an antihistamine.

A grand jury charged Catauga Caldwell, 27 and Melyssa Caldwell, 21, of Collings Lakes, with aggravated manslaughter, endangering the welfare of a child and manslaughter in the April 20 death of their baby, Atlantic County Prosecutor Theodore Housel said.

The couple was arrested today at a home in Clayton after the grand jury returned the indictment.

Housel would not release details of the baby's death, including the infant's gender. He said New Jersey State Police received a 911 call about an unresponsive child at the Caldwell home.

An autopsy performed by Atlantic County Medical Examiner Hydow Park determined the primary cause of death as promethazine intoxication.

Promethazine, according to Web sites WebMD and Drugs.com, is an antihistimine used to treat allergies. It also is used as a sedative or a sleep aid and treats nausea, vomiting or pain after surgery.

"It is alleged the parents administered the medication,'' said Pam Keelan, spokeswoman for the prosecutor's office.

The couple are being held in the Atlantic County jail in lieu of $250,000 bail each. If convicted of aggravated manslaughter, the most serious charge, they would face at least 10 years in prison.